A bottom-up approach to tractor safety : improving the handling of foldable roll-over protective structure (FROPS) through user centred design

Tractor rollover is the main cause of fatal and non-fatal accidents in agriculture; fitting Rollover Protective Structures (ROPS) on tractors is the most effective solution to prevent deaths in case of rollover. Foldable Rollover Protective Structures (FROPS) have been developed to facilitate tractor operation in low overhead clearance zones. However, many fatalities and serious injuries in tractor rollover accidents occur when the FROPS is left by the operator in the folded-down position after passing an obstacle. Little is known about the reasons of such behavior and few solutions have been suggested to overcome this issue. In the present study an ergonomic multidimensional analysis of FROPS operation considering users' critical behaviors and perceptions in their interaction with the tractor features were assessed, to develop user-centred design solutions to improve the manual handling of FROPS. A group of farmworkers (n=21) was observed and interviewed while handling the FROPS on their own tractor, to point out critical behaviors, perceptions of effort and discomfort, and suggestions for technical improvements. A set of FROPS-related objective measurements including the forces required to operate the foldable roll-bar were also taken. The participants reported moderate levels of perceived effort, as the entity of the force required to operate the FROPS was minimized by the low handling frequency. The observations pointed out some postural criticalities affected by FROPS technical features; moreover, the participants adopted some spontaneous strategies to facilitate the handling of the roll-bar which in some cases increased the exposure to the risk of falling. Based on the present results some recommendations for technical adjustments are proposed to encourage the correct use of FROPS thus preventing fatal accidents due to tractor rollover.